Technical Field
The present disclosure generally relates to paper strings and straps and, more particularly, to repulpable paper straps formed by pultrusion.
Description of the Related Art
Strapping machines are often used to bundle objects. Strapping machines can apply straps about a stack so as to bundle those objects together.
In some instances, conventional straps used to bundle objects, such as pulp bale, have been made from wire, steel, and plastic. Use of such materials for pulp bales has proven to be problematic because pulp bale often has to be repulped along with the strap. Repulping thus may be hindered because straps made from materials that do not support repulpability would have to be removed prior to initiating the repulping process.
To address such problems, typical solutions have included using straps made from paper for bundling pulp bales. Such conventional paper straps may be produced by twisting paper into strings, cords, or twines. In some instances, conventional paper straps may be produced by folding paper strips into a paper strap. In other instances, conventional paper straps may be produced by a combination of folding and twisting paper strips into a paper strap.
Conventional paper straps, however, have resulted in paper straps having limited strength and in some instances additional difficulties in repulpability, in addition to an increase in manufacturing costs. For instance, conventional paper straps may require tight twisting to retain the string in its consolidated and cylindrically round shape, further adding to lengthy and costly manufacturing processes. Similarly, folded paper straps may require paper strips to be folded at one or more locations to form the paper strap. The multiple twists and folds in paper straps may cause the fiber and paper orientation to be continually changed, which results in the loss of strength of the paper strap. Further, the twists and folds may inhibit water penetration into the paper straps which, again, hinders repulpability of paper straps. As a result, typical solutions to address the loss of strength may require using bulkier, and thus, costlier base paper. Other solutions may require adding synthetic fibers to improve tensile strengths of conventional paper straps. However, synthetic fibers, such as rayon, glass, nylon, polypropylene, polyethylene, etc., may hinder paper strap repulpability and machine runnability.